Note: Descriptions are shown in the official language in which they were submitted.
--2--
BACKGROUND
Techniques for the operation of gas wells
producing from petroleum reservoirs vary substantially
notonly fromgeologic regionto resinbut alsoamong wells
producing from a given reservolr. Commonly, flowing
gas wells are adversely affected by accumulations
within the well casing and tubing of liquids usually
comprised of oil and salt water. As such fluids accu-
mulate, the gas flow production of a well may diminish
10 to the point of failure in consequence of the static --
pressurebuild-up within the tubing and/or casing. To
achieve an optimization of the production from the
well, therefore, the well operator is called upon to
monitor pressure related parameters of this perform-
ance. Generally, any given well will exhibit its own
unlque performance "signature" which may itself vary
with time.
A conventional approach for correcting for
liquid build-up in a gas well involves a procedure
20 referred to as "intermitting"; a cyclically performed
operation wherein accumul~ted liquid is forced out of
the well under gas pressure. In a typical intermit-
tlng procedure~ mechanical clock-type controllers are
; provided which operate on a regular time cycle over
repeating twenty-four hour intervals to periodically
vent the well to the atmosphere and effect forcible
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expulsion of the liquld wlthln the tublng strlng.
Ventlng to the atmosphere now ls considered disadvan-
tageous both from an envlronmental standpoint as well
as in consequence of the waste of valuable natural
gas. As a consequence, other techniques now are gen-
erally employed. Another intermitting technique which
has been utilized provides for the pressure monitoring
of the tube string and casing of a given well. The
system is based upon the observation that the appro-
10 priate time to clear a well can be determined by not-
ing the differential in pressure between tubing and
casing. This differential, in general, will represent
the height of the fluid in the tubing above the bottom
of the well. When the well monitors indicate that a
predetermined differential in pressure is present, a
motor valve is automatically opened to provide for
fluid expulsion. See for example, U. S. Patent No.
3,266,574. In another arrangement, for example as
described in U. S. Patent No. 3,ô63,714, a control i8
20 provided wherein the well is vented periodically in
correspondence with the pressure within the tubing
string. The output of the tubing string of the well
is controlled by a motor valve, which in turn, is op-
erated by pressure pilot valves responsive to the rate
of flow and the differential existing between the
sales and tubing lines to determine the producing
interval.
il~5386
In some geologlc regions, for example in the
Applalachian reglon, as well as regions ln the Fort
Worth basin, flowing gas wells are very difficult to
produce. As a consequence, other techniques o~' prod-
uction are required. For example, most such wells
cannot merely be "intermitted", but must be produced
on a cycllcal basis. This technique involves a "shut-
ting-in" procedure wherein the well is closed for a
carefully determined interval of time sufficient to
10 allow well pressure to build up sufficiently to expel
all fluids upon subsequent opening up. Production
only OCCUl'S during that relatively short interval
wherein fluid and gas are expelled into the sales line -
system. The well then again is shut-in to achieve
necessary pressure build-up. As is apparent, the tim-
ing of these operations is critical. For example, a
typical well may produce for a twenty minute interval j-
~'ollowing which it must be shut-in for an interval of
~'our hours. Because the duty cycle of the well is so
20 short, deriving an optimum formula for producing it i~
becomes a taxing endeavor. Many pro~uction parameters
are considered, no two wells exhibiting the same per-
formance signature. Particular note may be made of
the economics associated with only minor changes in
the production interval. For instance, a four minute
deletion from a twenty minute production interval
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represents a ~0% loss ln sales revenue. Further,
failure to shut-in such a well within mere minutes of
the proper time envelope of productlon well may result
in a complete loading up of the well. This represents
a failure which may be very expensive to correct. One
technique for correcting for "loading up" is to shut-
in the well rOr an extended interval of time, e.g. 48
hours.
The tubing string in wells within the no~ted
10 region generally incorporates a plunger lift device.
With this arrangement, when the well is shut in, the
plunger is situate in the lowermost portion of the
tubing string. As gas pressure develops within the
well during the shut-in interval, fluid accumulates in
the tubing string above the plunger. At an optimum
point in time, a motor valve coupled between the tub-
ing string and separation and collection equipment is
opened to permit the plunger to be propelled to the
surface and fluid and gas which has collected above
20 the plunger within the string is delivered into the
sales system. Through the use of separation stages
and the like, the liquid is segregated from the gas
and the gas cap~ for the production interval, 1s re- -
covered. For the most part, control over these wells
has been one based simply upon a somewhat crude
clock-operated device, the cyclical closing and open-
; ing of a motor valve being determined by the operator
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followlng the periodlc monitorlng of a variety of
parameters such as the differential pressure between
casing and tubing strlng, sales llne pressure, experi-
ence with ad~acent wells, etc. With such monitoring,
the slgnature of the well, i.e. the perlodic develop-
ment of pressure differentials optimum for producing
and shutting in are determined and the cloc~ controls
are ad~usted accordingly. Such periodic operation of
the wells is found to be inadequate in many casès and
10 the fallure to accommodate for the various conditionswhlch can exist for a given well may lead to a load-
ing-up wherein expensive swabbing procedures and the
like are required to clear the t~bing. While the pe-
riodic shuttlng-in and opening of a well to produce it
is deslrable, the controllers avallable in the art
exhibit many deficiencies by virtue of their incapa-
bility of responding to a broad variety of operational
n~r~m~t.~, ~r ~p~ t. W~ 1 1 h~ h~hl~ ~?hl~
to develop an easily ad~usted on-off cycle accurate to
- 20 withina minutewhich extendswell beyond tuenty-fourhour
lntervals. Where conventional controllers are ad~ust-
ed, for example, to operate at a 48 to 72 hour cycle,
the incremental timing interval must be expanded ac- -
cordingly to 4 to 6 minutes. The latter trade-off
; generally is considered unacceptable. Further, condi-
tions often will be encountered where the cyclical
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tlmlng system must be overridden and subsequently re-
intiated on an automatlc basis. For example, should
the tubing pressure at the well head fall to a certain
predetermined level an indication may be present that
gas is not finding its way up through the tubing
string and that liquid is building up. Accordingly,
such a situation may represent an overriding condition
calling for shutting in the well. Other conditions
' may relate to the safe operation of a gas production
10 system. For example excessive liquid levels in
separating systems will call upon an overriding of
well cycling. Line pressure fluctuations may have a
particularly deleterious effect upon the production
of a well and production controls should be capable of
monitoring for such conditions and reacting according-
ly. In effect? a broad variety of conditions can be
contemplated for monitoring and reaction to achieve
the optimization as well as automaticn of flowing gas
well production.
SUMMARY ~
The present invention is addressed to an
improved flowing gas well control system and apparatus
in which the well operator is given a wide latitude '
of control in seeking the optimization of well produc-
tion. Utilizing a controller incorporating solid
state digital electronics greatly expanded production
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and shut-~n cycle lntervals are available with h,i~hly
accurate time-out techniques. A liquid crystal read ,
out mounted within the housing of the controller of '
the system serves to apprise the operator of ongoing
cycle timing conditions as well as to provide informa-
tion as to energization states and motor valve status.
.The flexibility afforded the operator with
the apparatus' of the invention, for example, permits
the well to be shut-in for an extended interval, e;g.
10 48 hours to correct for a loading up, following which
the system may be produced for short, accurately con- -
trolled production intervals, e.g. 20 minutes and sub-
sequent lengthier shut-in periods, e.g. 4 hours. Such
a program may be inserted by the operator with only one
simple adjustment.
Through the utilization of CMOS circuitry,
the controller may be powered over extended periods of ~
tlme by inexpensive, locally available batteries such ~'
as D-cells. To assure properly powered performance,
20 the control circuit of the controller incorporates a ;
low voltage level warning system having an output at
; the liquid crystal display which flashes'at a prede-
termined frequency for enhancing visual perception.,
In operating the system of the invention,
' , the operator inserts desired cycle times which may
range to about 100 hours for each off or each on cycle
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through the adJustment of binary coded decimal switch-
es mowlted wlth the control housing. Such adJustment
is made for each of the on and off cycles desired.
The controller also incorporates two manually actuated
switches which serve either to commence a shut-in
cycle time-out function of a production cycle time-out
function. The circuit serves advantageously to buffer
the output signal generated through actuation of these
switchesand theseswitches maybe utilizedto override an
lO ongoingcycle function atthe optionof the operator.With
the actuationof anyof these switches,the controlcircuit
of the system serves to reset the frequency generating
function thereof so as to provide appropriate accuracy
As another feature and ob~ect, the invention
provides a flowing gas well control system affording
the operator broad flexibility in monitoring a signi-
~ ficant number of parameters within a gas well facility
; lnis is accomplishea ~nrough ~ne use OI norma;ly o~en
switches associated with sensing devices. The switch-
20 es are coupled to the controller of the system through
a common terminal connected preferably with the off-
state switch function of the controller. In one ar-
rangement, a magnetically actuated proximity switch is
utllized to sense the position of a plunger as it
reaches the well head bumper. The switch may be ut-
illzed to commence off-cycle timing. In another
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arrangement, a gas pressure actuated normally open
swltch ls utllized in con~unction with the pressure
levels developed withln the tubing strlng itself to
carry out the commencement of an off or shut-in cycle
timing phase. In still another arrangement, a pres-
sure operated normally open switch is utilized in COIl-
~unction with sales line pressure. Once such pres-
sure reaches a prohibitive level, the switch is actu-
ated to, in turn, cause the well to shut-in for a pre-
10 determined off-cycle interval. Similarly, a normally
open .pressure actuated switch may monitor casine pres-
sure at the well head such that when the pressure
wlthin the casing reaches a predetermined level an off
or shut-in cycle automatically is commenced.
Another feature and object of the lnvention
resides in the provision of monitoring devices within
the separator and storage tanks of an installation. -
In this regard, a liquid level responsive gauge may be
positioned within the separator itself as well as
20 within a storage tank to provide automatic off-cycle
switch actuation and consequent shut-in cycling. In
the same regard, the flow rate of gas within the sales
line may be monitored and, should such rate fall below
a predetermined level, a normally open switch is clos-
ed to carry out motor valve actuation to derive a
shut-in state.
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Another object and feature of the invention
resides in a unigue shuttle valve incorporated within
the controller housing itself. This valve is actuated
from the control circuitry of the device through the
utilization of two tractive electromagnetic devices.
Other objects of the invention will, in
part, be obvious and will, in part, ap~ear hereinafter.
r~enerally stated, the present invention provides
an improved controller for actuating a motor valve in a
fluid hvdrocarbon well installation of a variet,v having
a motor valve actuable in response to an on or off designated
pneumatic state between open and closed orientations to
derive respective producing and shut-in conditions of
performance for the installation the improved controller
for actuating the motor valve, comprising: means providing
a d.c, source of power; pneumatic valve means connectable
between a source of gas under pressure and the motor valve
and including electromagnetically actuated valve means
energizable from the source of power to direct the gas under
pressure to effect respective the motor valve actuatina on
and off pneumatic states; oscillator means coupled with the
power supply for deriving a pulse train of predetermined
stable frequency; frequency divider means includins
multi-staae solid-state ripple carry counters for deriving at
least one pulse train of freauencv fl; displa,v means selectively
energizable from a plurality of driver input signals thereto
to provide multi-segment derived visible indicia representative
of time in hours and subdivisions thereof; manually programmable
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swiich means coupled with the source of power for generating
binary coded decimal signals representative of selected time
intervals represented in hours and subdivisions thereof
for each said designated pneumatic state; signal treating
for receiving the binary coded decimal signals and responsive
to a selected state input select signal and for providing
corresponding binary coded decimal signals at the outputs
thereof; binary counter means coupled for receiving the
co-rresponding binary coded decimal signals from the signal
treating means and responsive in the presence of an asserted
load signal and count command signal to incrementally alter
the received binary coded decimal signals in diminishing
arithmetic progressional fashion and provide the initial
received and altered binary coded decimal signals at outputs
thereof and deriving a carry-out signal at the termination of
the diminishing arithmetic progression; driver means connected
for receiving the binary counter means initially received and
altered binary coded decimal signals to derive the driver
input signals asserted at the display means; off-state
switch means actuable to derive an off-start signal; on-state
switch means actuable to derive an on-start signal; and
control circuit means responsive to a off-start signal and
a carry-out signal occurring at the termination of an on
designated pneumatic state and including timed switching
means for effecting the energization of the electromagnetically
acutated valve means for a predetermined interval, for
simultaneously generating the load sianal and the count command
: signal at the frequency, fl and responsive to a on-
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start signal and a carry-out signal occurring at the term-
ination of an off designated pneumatic state for effecting
the energization by the timed switching means of the
electromagnetically actuated valve means for a predetermined
interval for simultaneously generating the load signal and
the count command signal at the frequency, fl.
The invention, accordingly, comprises the system
and apparatus possessing any construction, combination of
elements and arrangement of parts which are exemplified in
the following detailed disclosure.
For a fuller understanding of the nature and the
objects of the invention, reference should be had to $he
following detailed description taken in connection with th~
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a sectional schematic view of a
flowing gas well installation with components shown sectionally
and out of scale;
Fig. 2 is a front elevational view of the control
panel of a controller according to the invention with
portions broken away to reveal internal structure;
Figs. 3A and 3B, when combined having Fig. 3B
placed to the left of 3A, provide a schematic representation
of the control circuit of the controller of the invention;
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Fig. 3C provides a schematic representation
of a swltch arrangement utili~ed in con~unction with
the circuit portion of Fig. 3B;
Fig. 4 is a block diagramatic schematic
drawing showing the system of the invention; ~-
Fig. 5 shows a series of logic waveforms
generated in con~unction with the operatlon of the
circuit of Figs. 3A-3B; -~ -
Fig. 6 is a sectional schematic view of a
lO valve used in connection with the controller of the
invention;
Fig. 7 is a partially sectional and ele-
vational view of a valve utilized in con~unction with
the controller of the invention;
Fig. 8 is a sectional view of the valve of
Fig. 7 taken through the plane 8-8 thereof; and
Fig. 9 is an elevational view of an electro-
magnetically driven valve used in con~unction with the
valve of Fig. 7, with portions broken away to reveal
20 lnternal structure.
DETAILED DESCRIPTION
The operational production of a flowing gas
well~essentially is an heuristic procedure involving
the variable performance parameters of tubing string
pressures, well head pressures, sales line pressures,
location of operational components wlthin the tubing
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strlng, llquid levels wlthin separators and storage as
well as gas flow rate indications. Inasmuch as these
parameters may vary wldely from one well installatlon ~
to another, the optimlzatlon of the production of any
glven well lnstallation has been found in the past to
be most elusive. To galn some insight into the prod-
uction requirements for a well installation, a typical
flowing gas well is schematically portrayed,in Fig. 1.
Referring to that figure, a well installation as might
10 be found, for example, in the midwestern region of the
United States is revealed generally at 10. Installa~
tion,10 includes an elongate casing 12 which extends ,
through the terrestrial surface 14 to a strata 16. - '
Generally, strata 16 is present as porous rock over
which an impervious cap is located. The resultant
formation serves as a form of pressurized reservoir
for oil, gas, water and the like. While the tech-
niques for penetrating strata 16 with casing 12 varies
from installation to installation, generally, the
20 outer surface of the casing is sealed with convention-
al cementing procedures, this seal be'ing represented
at 18. Access to the strata or formation 16 following
the placement of seal 18 may be provided utilizing a
variety of techniques, for instance, controlled ex~ ;
plosions. Surface control over the well is maintain-
ed by a well head 20 extending above surface 14.
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Head 20 incorporates appropriate hangers and seals
which serve to support a tubing string 22 which ex-
tends, for example, from the vicinity of well head 20
to an open lower end 24 situate in the vicinity of the
lower level of casing 12. In some installations, a
plurality of tubing strings 22 are utilized, each ex-
tending to a predetermined geologic formation to evolve
production at that location. The figure further re-
veals the presence of a plunger or "rabbit" 26 near
10 opening 24. The device is prevented from moving
through the opening 24 by a constriction 28. With the
plunger lift arrangement, well installation 10 is op-
erated on a cyclical basis, being shut-in for an in-
terval during which gas pressure gradually elevates
within casing 12. Additionally, a liquid generally
:
comprising oil and salt water, as at 30, accumulates
~ within casing 12 which gradually migrates through tub-
; ing string 22 above plunger 26, as represented at 32.
Plungers as at 26 are available to the industry from
20 a variety of sources, for example Axelson, Inc.,
Longview, Texas.
At a point in time ideal with respect to the
pressure of gas within casing 12 and the level of
accumulated liquid 32, a motor valve, shown schematic-
ally at 34, is opened which causes plunger 26 to be
propelled from the lower end of the tubing string 22
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under the influence of the accumulated gas pressure.
As this occurs, the liquid and gas above plunger 26
moves through a horizontal, T connectlon 36 and the
open motor val~e 34 to be directed into conduit 38,
representing the initial component of a sales line to
a separator 40. Separators as at 40 are provided in
the variety of configurations, that illustrated being
schematically representative of a single tube horizon-
tal device. The gas and liquid mixture enters sep-
10 arator 40 from tube 38 whereupon its velocity and di-
rectional flow are altered to permit falI-out of
heavier liquids to the bottom of the tank, as repre-
sented at 42. Gas and spray are collected in the up-
ward portions of the separator 40 wherein smaller
droplets coalesce to larger ones to join the fluid at
42 and, following final liquid particulate removal, as
through mist extractors or the like, gas enters outlet
conduit 44 of the sales line. By approprlate manipu-
lation of valving as at 46, the collected liquids 42
20 are drawn from separation stage 40 through a conduit
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as at 48 to be introduced to an oil and water storage
facility, represented by tank 50. Here the oil and
water is retained at variable levels, as represented
at 5~, a natural form of separation taking place prior
to its removal as by trucking or the like by communica-
tion through valve 54.
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ll~S386
-16-
Returning to the well structure, as the
plunger 26 is propelled under gas pressure, it passes
T-connection 36 whereupon it encounters a bumper
structure and/or lubricator 56. The plunger 26 re-
mains at this upward location against the bumper
structure until gas flow rate diminishes to an extent
permitting it to fall under gravity to its initial ~
position against, for example, constriction 28. To
permit optimized production for the well installation
10 10, motor valve 34 is closed to shut-in the well for
an interval of time prior to the commencement of a .
next.plunger lift and removal of the gas cap. As in-.
dicated hereinabove, the production and shut-in cycles
providing optimumproduction varies from well to well.
; As a consequence, the well technician is called upon
to ex.amine varlous parameters of its initial perform-
ance to derive a form of signature representing the
be~t cycling of the well through the openlng and clos-
ing o~ motor valve 34. Usually, this initial evalu-
~ 20 ation ~s carried out by obser~ing the differential
.pressure between tubing string 22 an~ casing 12. This
difference, in general, represents the height of fluid
32 above plunger 26. When the timing of such pressure .
responses is determined for optimum production, a con-
troller, in the past being provided as a mechanical
clock operated device, is preset to provide sequen-.~ .
tially occuring off and on or shut-in and producing
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states of performance for the lnstallation 10.
A controller for carrying out the timing of
the cyclical operation is represented generally in the
flgure at 60. Controller 60, at appropriate cyclical
intervals, applies or releases lower pressure drive
gas, i.e. at a pressure of about 25 p.s.i.g., through
a conduit 62 to the diaphragm drive of motor valve 34.
The supply of this lower pressure gas is derived from
the well head as through conduit 64 which leads to a
10 filter and regulator 66 and thence to the input of a
control valve positioned within controller 60.
As is apparent, it is desirable that the
cycling interval capability of controller 60 be as
broad as possible to permit efficient production.
Where the cycling time availability is llmited, for
example to the twenty-four hour capability of current
devices, the well cannot be produced at highest effi-
^ ^ ~ ^ ~' ~ ~ A ~ r ~ A ~ ~ 1 1 J~ ~ Y ~ ~ ~ JT ~ ~ ~ t ^f 2~ ~ptl~.i_ed
program. As this occurs, the well may be "loaded up"
20 to an extent wherein the fluid ~2 is of such a height
prior to opening valve 34 as to render the movement of
plunger 26 impossible. With the present invention,
greatly expanded periods for each cycle are available
to the operator. The controller additonally enjoys
the capability of monitoring a p~urality of other
production parameters to provide and override over the
otherwlse dominant cyclical controlof motor valve 34.
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Looking addltlonally to ~ig. 4, parameter
controls represented in Fig. l are shown ln block dia-
grammatic fashion. Where the same functions or com-
ponen~s as are described ln Flg. 1 are again repre-
sented in Fig. 4, identical but primed numeration is
utillzed in the latter figure. Fig. 1 sho~s the pre-
sence of a switching gauge 70 connected to well head
20 in a manner wherein it monitors casing pressure.
Should this pressure continue to fall to a dangerously
10 low level following the opening of motor valve 34, an
i~dication may be present that liquid is building up
in the tubing and casing faster than it is being ex-
pulsed. Accordingly, the operator may wish to over-
ride a timed production cycle and shut-in the well
upon this pressure reaching a certain level. As shown
in Fig. 4, the commumication between casing pressure
monitor 70' and well head 20' is represented by line
72, while the electrical indication generated by func- -
tion 70' is shown being introduced to controller elec,
20 tronics block 60' as along line 74. Pressure respon-
sive switching gauges whlch may be utilized as above-
described are available in the market, for e~ample be-
ing produced by Frank W. Murphy Manufacturing, Inc.,
Tulsa, Oklahoma. Generally, a normally open, single-
pole--single-throw switch which cIoses at a programmed
pressure level is incorporated within such gau~es.
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The figures further reveal the presence of a
magnetically actuated proximity switch 76 positioned
ad;acent the upper extension of tubing string 22 and
somewhat adjacent bumper 56. This switch is-actuated
when plunger 26 is in its uppermost orientation. In-
corporating a normally open switch which is closed
upon the plunger 26 reaching that upward orientation
the switch affords the development of a production in-
terval which is determined by the physical movement of
10 plunger 26 as opposed to the utilization of a prede-
termined fixed interval. The magnetic association be-
tween plunger string 22' and the proximity switch 76'
is represented in Fig. 4 by line 78, while the elec-
trical signal to controller electronics 60' is repre-
sented by line 80.
Positioned upon conduit 38 on the sales line
side of motor valve 34 is another switching gauge 82
which serves to monitor the line pressure aspects of
the gas distribution system. Particularly where com-
20 pressors and the like are incorporated in such distri-
bution systems, high pressure fluctuations may be en-
countered. Where such line pressure exceeds predeter-
mined limits it is important to override the operation
of the well, inasmuch as plunger 26 may be prevented
from performing a full cycle whereupon the well will
rapidly commence to be loaded up to the point of fail-
ure. Accordingly, as represented in Fig. 4, gas
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~l~S386
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pressure at the sales line ls monitored by function
82' by connection therewith, as represented by line
84. Where such pressure exceeds predetermined value,
an input is provided along line 86 to the electronics
of controller 60'.
Another parameter of operation over which
monitoring may be desired is that of the velocity of
gas as it is initially presented to the sales line.
Fig. 1 reveals the presence of a flow rate switching
10 gauge 90 measuring the differential gas pressure a- -
cross a restriction within line 44. For any given tub-
ing geometry at given pressure there exists ~ critical
gas velocity below which liquid will not be entrained.
The switching flow meter type pick-off as at 90 can be
utilized to monitor such an input and cause the well
to be shut-in where such liquid velocities are not
maintained. Fig. 4 reveals the instant function at
90' coupled to line 44' through line 92 and providing
an input to the electronics of controller 60' through
20 line 94. This input preferably is provided by closing
a normally open switch. Fig..4 additionally shows the
conventional measurement of tubing pressure at block
96. The association of function 96 with the tubing
strlng at an outlet T thereof is represented by line
98, while an electrical signal representative of low
'`,, tubing pressure of the like may be provided along line
100 to the electronics of controller 60'.
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~llS3~6
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In addltlon to the performance monltorlng of
the installation 10, monltors additionally may be pro-
vided looklng to the safety aspects of well system
performance. For example, a normally open high liquid
level responsive switch may be provided both within
separator function 40 as well as storage tank 50.
Fig. 1 shows such switches respectively at 102 and
104. Liquid level responsive switches are available
in the market, being produced, for example, by Dover
10 Corporation, Norris Division, Houston, Texas. Fig. 4
shows the liquid level monitoring functions at 102'
and 104', separator monitoring being represented by
ll~e 106 with switching input line to control elec-
tronic 60' being provided at 108 and storage level
monitor 104' being associated with the separation and
storage facilities through line 110 and providing a
swltching input to controlier electronics 60' along
line 112.
Upon the assertion of one of the various
20 monitorlng switching inputs to the electronics of con-
troller 60', the motor valve 34 may be closed, ~or
example, by the electrical actuation o~ a shuttle
valve or the like and consequent development of or
release of pressure within line 62'. With the use of
the control electronics of the instant invention, the
well operator is afforded a broad choice of controls
ll~S3~G
-22-
over any given installation. For example, varlous
parameters can be comblned in typica.L gating proced-
ures to apply any series or combination of inputs to
develop a control over motor valve 34'. As a conse-
quence, ~uch improved opportunity for optimizing the
productlon of wells is availed.
Looking to Fig. 2, the face plate conta~ned
within the weatherproof controller housing 60 is re-
vealed at 120. This face plate carries a visual in-
10 formation output as well as components requiring re-
placement.or manual setting in the course of well oper-
ation. For example, a switch 122 may be depressed to
commence the timing of an "off" cycle wherein the well
is shut in or pressure is off the diaphragm of motor
valve 34. Correspondingly, the manual depression of
switch 124 commences the timing for an "on" cycle
wherein pressure is on the diaphragm of motor valve
34, or the well is produced. Immediately beneath
switches 122 and 124 is a numerical readout component
: . 20 126 which is shown, for illustrative purposes, to be
reading 88 hours and 88 minut.es. The presence of a
period between the 88 hours digits represents that
pressure is on the diaphragm of motor valve 34. Cor-
respondingly, the presence of such a period between
the 88 minutes digits represents that pressure is off
the diaphragm of the motor valve. The colon inter-
mediate the hour and minutes notation is selected to
`' .
~. .
, I
:'
.
li~S3~6
-23-
osclllate to show the presence Or a power on conditlon.
Addltionally, a blinking of the hours digits ~s uti-
lized as a low battery level indicator. Beneath the
numerical readout 126 are banks of num~erically ad-
justed rotary input switches representing cycle time
wherein pressure is on the diaphragm of motor valve 34
respectively for hours and~ minutes at 128 and 130.
Correspondingly, rotary switches for inserting desired
cycle times wherein pressure 1s off the diaphragm for
10 hour and minute designations are represented respect-
ively at 132 and 134. A power supply for the entire
assembly is provided within an appropriate battery
container 136 which is readily accessible to the op-
erator. With the utilization of CMOS type electronics
withln the controller, such batteries have a very long
life span, for example in the range of about eight
months. The wiring input from the above-noted exter-
nal parameter functions is conveniently provided at
the base plate 120 at normally open switch terminals
20 138.
Loo~ing now to the control circuitry of the
invention, a distinct advantageto theutilization of
the control technique of the invention resides in its
very low power consumption, coupled with a greatly
broadened capability of control. This desirable op-
eration is achieved preferably through the use of
COS/MOS components which ideally consume power only
during logic transitions. Further, the components
. ~.
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' ' ' ' ' '
.
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ll~S3~;
-24-
generate almost no switching noise, provlding perhaps
the quietest of gating systems. Inasmuch as such com-
ponents now are available in multi-function form, the
commercial designations thereof are provided herein
where appropriate. To facilitate the description to
follow, when the inputs or outputs of a component are
at ground or appropriately pass a corresponding ref-
erence potential, they are referred to as "low".
Conversely, when these inputs or outputs assume or
lO approach the voltage status of the ~owersupply, they
are referred to as being "high".
In its general operation, the control cir- !
cuit of the invention incorporates ripple carry count-
ers into which are inserted the on cycle and off cycle
tlme data through operator manipulation of the switch--
es as described at 128-134 in connection with Fig. 2.
This data is inserted through drivers to a liquid
crystal display to give the operator a visible indicia
of the state of any given cycle. Upon pushing an on
20 or off start switch, an electromagnetically actuated
valve is properly positioned to control the motor
valve 34 for a shut in or producing state and the
counters are activated to commence to count down from
the time values inserted through the above-noted
switches. At the termination of a given cycle, a
carryout signal serves to cause the cycle to automat-
ically commence counting down the time interval
' - ~ '' '
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1~ 53~6 .
.
--25-
selected for the next successive operational state,
i.e. an Orr state following an on state. Various
other aspects of the circuit and system will become
apparent as discussion thereof unfolds. For the pur-
pose of clarity, in the foregoing description of Figs.
3A and 3B, Fig. 3B should be considered as ~uxtaposed
to Fig. 3A in accordance with the bracket and labels
appearing thereon. Basic pulse train input to the
circuit is provided by a logic gate oscillator with
10 crystal control. The principal components of this
function are present as a 1.11848-MHz quartz crystal
- operating in con~unction with a fourteen stage ripple-
- carry counter 152. The latter component may be a
model CD4060BE produced by RCA Corporation, Solid
State Div., Somerville, New Jersey. When connected in
conventional fashion as shown with bias resistor 154
and capacitors 156, 158 and 160, counter 152 serves as
an accurate and stable time base, providing a
273.07 Hz pulse train output at llne 162 as well as a
20 68.27 Hz pulse train at line 164. Counter 152 is a .
generally basic structure ? typically implemented with
~-k flip flops, the output of successive ones being
connected to a next following flip flop input to pro-
vide count propagation in sequential order. Power to
counter 152 is asserted from a six volt battery supply
connected from lines 166 and 168, while ground coup-
ling to the counter is derived from lines 170 and 172.
.
. .
! ~ . . .
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' ' ' , ' ', ' ' '" ' ', ~' ' ~
,: ., ' . ' '' ' ' ' ~
"
~ S3~6
-26-
Counter 152 is coupled to a substantially
ldentlcal ripple counter 174 through llne 162. Count-
er 174 serves a frequency dividing function, providing
the principal clock frequency of 0. 016667 Hz or one
cycle per minute at its output line 176. The counter
also is tapped to provide a 1. 07 Hz output pulse train
at line 178 which will be seen to provide a colon
blinking action representinga ppwer "on" indication.
Further, the counter is tapped at line 180 to derive a
10 0.26 Hz signal which ultimately is utilized in con-
~unction with a low battery warning feature. As in
the earlier case, ground input to counter 174 is pro-
vided from lines 170 and 172, while power input from
the~e battery supply derives from line 166.
Looking momentarily to.Fig. 3C, a schematic
representation of the manually settable switches des-
cribed at 128-134 in connection with Fig. 2 is illus-
trated generally at 142. As revealed in the drawing,
the switch arrangement may be of a two-pole binary
20 variety, one set of four poles, represented at i84,
bPlng coupled to the posltive side of the battery
supply, while the opposite set of poles 186 are com-
monly coupled to ground. By appropriate manipulation
of a dial or the like, a binary coded decimal signal
(BCD) may be developed for insertion into the count
circuitry. Typical of such switches are those mark-
eted under the trade designation "stripswitch",
''' : .
.
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11~5386
-27-
model No. 21XX56G by E.E.CØ Corporatlon, Santa Anna,
California.
Returning to Fig. 3A. such switches as at
182 are set forth in block schematic fashion at Sl-S8.
The switches are arranged such t~at ;switches Sl-S4
provide time selection for a state wherein pressure lS
off the diaphragm of motor valve 34. Conversely,
switches S5-S8prov~de time data inputs for determining
the cycle wherein pressure is on the diaphragm of
10 motor valve 34. Looking to the off-condition switches,
switch Sl is positioned to provide BCD signals repre-
senting tens of hours through the grouping of four
~ leadsrepresented at 188. Switch S2 provides BCD sig-
~ nals in hour units through the grouping of four leads
190. Switch S3 provides BCD signals representing tens
of minutes through the grouping of four leads 192
and switch S4 provides BCD signals representing minute
. units through the grouping of four leads 194.
Looking to the corresponding "on" condition
20 of the switches, switch S5 provides BCD signal inputs
along the grouping of four lines I96 representative of .
tens of hours. Switch S6 providesBCD signals repre-
senting hour units along the grouping of four leads ~;
. 198. Switch S7 provides BCD signals along the group-
ing of four leads 200 representing tens of minutes and
: switch S8 provides BCD signals representing minute
un~ts along the grouping of four leads 202.
'` ~
.. : . '' . ' ' : , :.
-,
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- , . : . : : . ` .
` ' . ' : ,:- ~
ll~S386
-28-
Lead groupings 188 and 196 from respective
swltches Sl and S5 are directed to the input pins of a
quad, two-input multiplexer 204. Such multiplexers
are monolithic complementary MOS (CMOS) integrated
circuits constructed with N and P channel enhancement
trasistors. Incorporating select and enable inputs~
such multiplexers are marKeted underthe~model designa-
tion MM74C157by Pioneer-Standard Electronics. Inc.,
Dayton, Ohio. The four lead groupings 190 and 198 of
10 respective switches S2 and S6 similarly are directed
to the inputs of multiplexer 206. This multiplexer
may be identical to that described at 204. Similarly,
the lead groupings 192 and 200 of respective switches
S3 and S7 are directed to corresponding inputs of the
multiplexer 208, while lead groupings 194 and 202 of
respective switches S4 and S8 lead to the inputs of
multiplexer 210. As before, multiplexers 208 and 210
may be identical to that described at 204. Ground
reference inputs to multiplexers 204-210 emanate from
20 lines 212 and 214, while connection between the bat-
; tery supply positive output and each of the multi~ .
plexers is provided from trunk line 218. A blnary
select signal may be inserted simultaneously into each
of the multiplexers from along line 216. In the latter
regard,at such time as line 216 is high, the signal
lnformation presented by off-state switches Sl-S4 is
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- : . , : .
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lllS3~6
-29-
transmltted through respectlve multiplexers 204-210.
Conversely, when line 216 is at a logical low, multi-
plexers 204-210 transmit the information developed
from respective switches S5-S8.
The outputs of multiplexers 204, 206, 208
and 210 are presented at respective groupings of four
leads 220,222, 224 and 226, looking from the left ex-
treme toward the right for each of the multiplexer
symbols. These groupings of leads are coupled with
10 the inputs of respective synchronous four-bit up/down -
decade counters 228, 230, 232 and 234. The latter are
monolithic complementary MOS (CMOS) integrated BCD
counters. Typical of the components which can be
used for these counters are devices marketed as model
No. MM74C192 by National Semi-Conductor Corporation,
Santa Clara, California. The counters are cascaded by
the mutual lnterconnection of the countdown inputs
thereof with corresponding borrow outputs, for exam-
ple; as along line 236, connecting counter 228 with
20 counter 230; along line 238, connecting counter 230
with counter 232; and along line 240, connecting count-
er 232 with counter 234. The countdown input to count-
er 234 is supplied from along line 242. Ground refe^r-
ence input to each of the counters is derived from trunk
line 214 leadlng to ground line 212, while a load command
ls asserted simultaneously to each from along line 244,
loadlng occuring when that line receives a load
, .~
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- . . . .. . . ~ .
'' ' ' " " '
,
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~1~53~6
pulse. Positive reference power is supplied to each
of the counters, 228, 230, 232 and 234 from trunk
lines 246 and 248. Upon operating upon the data in- ~
puts thereto from line groupings 220, 222, 224 and
226, the counters provide countdown outputs thereof at
respective four line groupings 250, 252, 254 and 256
and, it ~y be noted, that the carry output of counter
228 is coupled to a line 259.
- Output groupings 250, 252, 254 and 256 are
10 connected to the corresponding inputs of drivers 258,
260, 262 and 264. These drivers may, for example, be
present as BCD-to-seven segment decoder/drivers de-
signed for use with liquid crystal readouts. General-
ly they are constructed with complementary MOS (CMOS)
enhancement mode devices and are marketed as model
No. Mc14543B from Motorola Semiconductor Products,
Inc., Phoenix, Arizona. The high level side of the
power supply is connected to the drivers from along
- trunk lines 246 and 248, while their ground reference
.
20 coupling is provided from along line 212. Phase in-
puts to each of the drivers 258-264 is inserted from
the output of counter 152 through lines 164, 266 and
268. The seven component outputs of drivers 258, 260,
262 and 264 are present at the seven line groupings
represented respectively at 270, 272, 274 and 276.
These outputs line groupings lead to the corresponding
", , . ~ ~
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~ .S3~6
-31-
lnputs of a seven segment liquld crystal display 278.
Such displays are characterized ln a very low current
demand, thus permitting the use of a convenient inex-
pensive battery power supply for the instant control-
Ier. Of course, it should be understood that other
forms of display incorporating light emitting diodes
(LED's) or the like may be utilized, but with a loss
of current conservation capabilities. Displays as at
278 are available, for example, as model No. 8655 mar-
10 keted by Shelly Associates, a subsidiary of Datatron,Inc., Irvine, California. The back plane of display
278 is driven from line 164 by application of the
68.27 Hz pulse output thereon deriving from counter
152. Liquid crystal displays as at 278 provide a
seven segment readout as typified at 126 in Fig. 2.
In this regard, four numerical digits are separated by
a colon and decimal points may be positioned at least
intermediate the external pairs of digits of the dis-
play. As noted above, the decimal point inputs are
20 utilized in the instant invention to show the oper-
ational cycle, i.e. the presence of pressure on or off
the diaphragm of motor valve 34, while the colon is
utilized to represent a power on indication. The i~-
puts to drive these indicia are presented from lines
280, 282 and 284, which extend from another driver
286. In this regard, line 280 provides the signal for
.~ .
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--32 -
drivlng the "on" declmal polnt; line 282 provides the
signal for drivlng the colon; while line 284 provldes
the signal for driving the "off" state decimal point.
Driver 286 may be provided as a four segment display
driver such as model No-CD4054AE marketed by RCA Cor-
poration (supra). The ground reference input to driv-
-~ er 286 e~anates from lines 288 and 290, the display~
frequency input thereto emanates from line 266 extend-
ing from line 164 and carrying the 68.27 H~ output of
10 counter 152. Additionally, driver 286 receives the
colon drive pulse frequency input at 1.07 Hz from a-
long line 178. This input is passed into the above-
described output lines by virtue of the connection of
; the strobe inputs of the driver with a constant high
voltage level, i.e. to the battery source as through
line 292.
Now turningto the logic control over the
above-described timing system, reference additionally
is made to Fig. 5. The latter figure provides voltage
20 timing diagrams for three logic conditions. Under
vertical column Aj certain voltage conditions are re-
vealed when the timer is on an arbitrarily selected
0.0:34 minutes remaining in an "on" cycle and the op-
erator presses the start "off" button as revealed at
122 in Fig. 2. Columns B and C of the figure provide
timing information respectively for the automatic
.~ .
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~-
;. : . .
~IllS3~6
transltion from an "off" to and "on" state and the
opposlte transition from "on" to "off". The latter
two transitions occur with switch Sl-S4 settings o~
01:30 (off) and switcll S5-S8 settings of 00:55 (on),
these setting being arbitrarily assigned for exemp]ary
purposes.
The start "off" switch button 122 shown in
Fig. 2 is represented in Fig. 3B as switch S9, while
corresponding "on" start switch 124 is represented at
10 switch S10 in the circuit diagram.
' With the closure of switch S9 or the equiva-
lent thereof through inputs from external monitors, as
described in connection with Figs. 1 and 4, line 294,
incorporating resistor 296, is coupled to ground
through lines 298, 300, 288 and 290. Line 294 is
coupled through a resistor 302 to the positive side of
the batterypower supply. As line 294 is coupled to
ground, a caPacitor 304 is dischar~ed throu~h resist-
,or 296, thus altering the voltage level at line 294
- ' 20 from a high to a low (See level III of Fig. 5). Line
294 is coupled to-the inputs of one NAND gate of a
four gate component delineated by dashed boundary 306.
Component 306 may, for example, be present as a
COS/MOS quad of two-input NAND Schmitt triggers mar-
keted as model CD 4093B by the Radio Corporation of
America (supra). The Schmitt triggeF feature of these
. , .
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S3~6
-34- -
devices permlts a desirable snap-action response wlth
a hysteresls or dead band. The transltion at line 294
causes llne 308,extendingf'rom the uppermost NAND gate
output, to assume a high value which is directed to
one input side of a NAND gate within four gate com-
ponent 310. Component 310 is identical to four gate
component 306. The opposite input to the sub~ect NAND -`'
gate within component 310 is normally high'by virtue
of its line 312 connection. Consequently, the output
10 of the gate at line 314 transitions to a low value.
This s'ignal is asserted through line 316 to a next
lower NAND gate within component 310 which is coupled
in similar fashion through a start switch S10. As
represented at level IV of Fig. 5, the low value at
line 314 represents the exclusive signal from switch
S9, the "off" start switch. The signal at line 314
is connected to one lnput of an exclusive NOR gate -
within a composite assembly of four such gates at 318.
Such composite assemblies as at 318 are marketed, ~or
20 example, by Radio Corporation of America, (supra) as
model No. CD4077B. The oppos~te input of the exclus-
ive NOR gate being coupled to ground through line 320,
the output thereof at line 322 transitions to a high.
This logic level, illustrated at level VII in Fig. 5,
rçpresents the signal to override any ongoing "on"
condition or state. The high value at line 322 is
,
~ " .
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' lllS3~16
-35-
transmltted through line 324 to the reset lnput of one
COS/MOS flip-flop of a composite, dual "D"-type flip-
flop represented within dashed boundary 326. Compon:eh,ts
as at 326 are marketed by RCA Corporation (supra) .
:; under the model designation CD4013. As the reset input
of the flip-flop is brought high, the Q output thereof
at line 328 transitions to a high (See level VIII in ` :
Fig. 5). Line 328 is coupled with line 216 leading to :
the select input to each of the multiplexers 204, 206,
10 208 and 210 to cause them to select the switching state :~
(off) determined at switch S9. This high signal at line
328 also is directed to one input of driver 286 to .
cause it to activate an appropriate "off" decimal point
status indicator through line 284. As is additionally
represented at level VIII in Fig. 5, the high level at
line 328 is asserted through line 33Q to the leading
edge triggering input of.the positive tripping input
1~ ~r ~rl~ multi-ViDrator wlthin the composite compo-
nent identified by a dashed boundary 332. Components .
20 as at 332 are marketed by RCA Corporation (supra) .
under the model designation CD4098BE. The leading
edge triggering occasioned by the signal at line 330
causes the Q output thereof at line 334 to exhibit a
high signal the pulse length of which is determined by
an R.C. timing network 336 incorporating capacitor 338
., .
:
-
~ 3~6
-36-
and timlng reslstor 340 connected as shown to circuit
timing lnputs of the multl-vlbrator (See Flg. 5, level
XIV). Note that resistor 340 is coupledto the posi~
tive voltage of the power supply of the apparatus.
The signal at line 334 is asserted through
resistor 34? to the base of the first NPN stage of a
Darlington connected transistor pair 344. As a con-
sequence, transistors 344 are turned on to, in turn, -
couple lines 346 and 348 to ground. Line 346 is coup- -
led to one side of a tractive electromagnetic drive ~
for a valve within controller housing 60, to be des-
cribed in detail hereinafter. The opposite side of
the input to the electromagnetically actuated valve ls
connectedthrough lines 350 and 352 to the positive
side of the battery power supply and lines 346 and 350
are mutually electrically isolated by a blocking diode
354. As a consequence of the energization of the
; electromagnetic components Or ~iliS valve? tho sys~em.
is altered to a state wherein pressure is imposed upon
the diaphragm of motor valve 34.
The Q output at line 360 of the upwardly
disposed flip-flop within composite component 326
transitions to a low upon the assertion of the high
input to the reset terminal thereof from line 324.
Llne 360 is connected through lines 362 and 364 to an
..
., ,~ ' ''.
. ' . ~
., ~
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115386
-37- ~:
R.C. timing network 366. Network 366 includes a
timlng resistor 368 coupled within line 364 and a -- .
capacitor 370, these components being commonly con- :~
nected to one input to an exclusive NOR gate formed
within a composite assemblage of four thereof as rep-
resented by dashed boundary 372. Composite component
372 may be identical to that described at 318. As
connected to the associated exclusive NOR gate, net-
work 366 serves to form therewith a pulse generator
.
function having a pulse output at line 374, repre-
sented at level X in Fig. 5 and ultimately utilized
for loading commands at line 244. Line 374 also ex-
tends to one input of an exclusive NOR gate within
component 372 and the opposite input to that gate de-
rives from line 376. The inputs to the exclusive NOR
gate whose output is coupled to line 376 derive from
lines 380 and 382, extending to an exclusive NOR gate
Wi~hill ~ rl~rr~ 3i8 ~oci~teu wi~h switcnes SiO.
The opposite input thereto derives from line 324 which,
20 by virtué of its coupling with line 322, is associated
wlth the orientation of switch S9. Accordingly, the
logic level at line 376 varies in accordance with the
position of switch S9. Therefore, the signal at load
line 244, for conditions wherein switch S9 is manually
actuated by depression and then release, will exhibit an
.111~3~6
-38-
output as ~epresented at level XI into ~lg. 5. Upon
manual release of swltch S9, the loglc level at llne 244
transltlons from a low to a high, however, the loading-
functlon will have been carried out. The former logic
alteration, however, ls utillzed for the purpose of re-
setting counter 174 from line 382. In this regard, it
may be observed that load line 244 is connected through
line 384 to a NAND gate within component 306, the output
of which is connected to line 382. The inverting func-
10 tion thus created permits a high to low transition to be
asserted through line 382 to accurately set the timing
function of the circuit.
. Line 384 additonally is connected to a second
gate within component 306 the output of which is present t
at line 388. Line 388 is j oined with line 176 at the in-
put to another exclusive NOR gate at component 372 hav-
ing an output at line 24? leading to the down count input
: to counter 234. As represented at level I in Fig. 5, ~
this exclusive NOR gate treatment causes the count down .
20 input at line 244 to provide an initial positive-going
cloc~ transition to immediately remove one minute from .
the display at 278. This arrangement is necessary,
inasmuch as the display would otherwise stay on 0.0:00
for one full minute as counter 174 divides a final :~
minute of a cycle and thereby add one minute extra to
the de~ired timed interval.
,
., ' ~
.. .
I
~- . .
:
: , . . .
,
'.
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1~5386
-39- -
As thus far described, the informational in-
put to dlsplay278 isof a decade configuratiOn. Con-
sequently, itis appropriate to convert the readout to
an hours and minutes representation. To carry this
out, when a carry pulse is received from counter 232 .
at llne 238, it is transmitted to the clock input of
the lower flip-flop within composite component 326.
This causes the Q output thereof at llne .406 to go
high, and the signal is asserted at the input to one
10 two-input NAND Schmitt trigger of a composite COS/MOS
quad two-input NAND Schmitt trigger identifed by dash-
ed boundary 396. This component may be identical to
that descrlbed at 306. The opposite input to that . -
NAND Schmitt trigger is from line 408 which extends to
the output line 162 of counter 152. Accordingly, a
273 Hz pulse input is supplied from line 408 through
. the NAND trigger to line 410 which extends to the up-
CGUiît ûf cour,ter 232. Thc rcsuitailt pulsc traill
rapldly runs the second digit of the display upward
20 through the numbers 0-4. When the BCD equivalent of
five is reached, a signal representing that number is
present at lines 394 and 398 of counter 232. These
lines form the input to another NAND Schmitt trigger ..
within component 396 having an output at line 400
leading to one input of still another NAND Schmitt
tr1gger therewlthin. The opposite input to that trlg-
. ~
-~ ~llS386
~ 40-
ger derives from llne 402 whlch is coupled to load llne 244.
The resultant low signal at line 404 is lntroduced to the
reset input of the lower flip-flop in component 326. In
consequence, the Q output thereof at line 4 o6 resets to a
high level to, in turn, stop the high frequency upcount
pulse train.
The circuit of the invention also provides an
indication of low battery power supply levels. The read
out indicating this condition is developed by periodically
10 blinkingthe first two digits in the display at 278 which
are driven by drivers 258 and 260. In this regard, it is a
characteristic of the NAND gates of component 369 that as
the voltage imposed thereupon at their inputs commences
to drop belowa normal or standard operating range for the
gate, the trigger level value thereof becomes variable or
non linear. This variance is to an extent wherein the trig-
gering voltage for the NAND trigger alters to a higher
percenta~;e of the now diminishing supply voltage input
level and ultimately approaches and reaches that level.
20 Accordingly a divider network is provided incorporating
divider resistors 416 and 418 within line 420. Line 420 is
coupled between battery supply voltage and ground and the
~unction between resistors 416 and 418 is connected along
line 422 to one input side of the NAND Schmitt trigger
withln oomponent 396. This provides the "supply" to the
trigger. The opposite input to the trigger emanates from
ll~S3~6
--41--
line 180 which provides a 0.26 Hz pulse train. Since the
input voltage level as defined by the divider network at
line 422 remains a fixed percentage of supply voltage, the
voltage asserted at input line 422 eventually drops to
cause the trigger to react by triggering and transmitting
the pulse train from line 180 to line 424. This signal is
invertedat a gate within component 318 and submitted
along line 426 to one input of drivers 258 and 260 to carry
out the blinking warning function.
Looking additionally to column B of Fig. 3C, the
automatic transition from an "off" state to an "on" state is
considered. While the curves shown in column B of the fig-
ure apply to the automatic transition as may be encountered
with operation fromthe settings of coltlmn A, columns B and
C, respectively, are described as at level XV in connection
with exemplary switch settings of 0:55 for an on cycle and
01~30 for an off cycle time.
No externally derived signal is needed to effect
the continuingcycle "off" to "on" transition. For exam
20 ple, a carry out pulse is generated by the final counter 228
at line 259. Line 259, ~i~ turn, leads to the clock input of
the uppeP flip-flop within component 326 (See levelXII,
Fig. 5). In consequence, the logic levels at lines 328 and
360 reverse and a positive going signal is asserted from
llnes 360 and 362 to the lower disposed one shot multi-vi-
brator transition terminal within component 332. This
causes the Q output thereof at line 430 to exhibit a high
. .
~llS3~6
-42-
signal,the pulse lengthof whlchis de~ermlned by an R.C.
timlng network 432. Network 432 includes a timing
capacitor 434 and timing resistor 436 connected, as
shown, to circuit timing inputs of the lower multi-
vibrator. Note, that resistor 436 is coupled to the
positive voltage of the power supply. The signal at
line 430 is asserted through a resistor 438 to the
base of the first NPN stage of a Darlington connected
transistor pair 440. As a consequence, transistors
10 440 are turned on to, in turn, couple lines 442 and
444 to ground. Line 442 is coupled to one side of a
tractive electromagnetic drive for a valve within
controller housing 60, as is discussed in detail later
herein. The opposite side of the input to that elec-
tromagnetically actuated valve is connected through
lines 446 and 448 to the positive side of the battery
power supply. Lines 442 and 446 are mutually elec-
trically isolated by a blocking diode 450. As a con-
sequence of the energization ofth-e electromagnetic
20 compor.ents of theroted valve, the system is altered to
a state wherein pressure is released from the diaphragm
of motor valve 34. Note also should be made that thé
signaltransitions at lines360 and 362 also are witnes-
sed through line 364 at network 366. This is the pulse
generator network which serves, as above described, to
provide a load line input. In the latter regard, re-
ference shouldbe made tolevel IXof column B of Fig. 5.
'
,....... . .
..
lliS3~6
- - 43-
As noted above, column C of Flg. 5 provides
logic data representing a transition from an "on" to
an "off" state where the off input switches have been
ad~usted to read: 01:30. As revealed at level XII,
when a carry-out pulse is derived from counter 228 at
line 259, a pulse is asserted at the clock input to
the uppermost flip-flop of component 326. This causes
level transitions at its ~ and Q outputs which are
carried by respective lines 328 and 360. The system
10 then commences to carry-out a countdown as earller
- described in connection with the depression of switch
S9. ',
For a manual commencement of an "on" state
of the control system, switch S10 is momentarily de-
pressed. Such closure of the switch serves to connect
lines 452 and 456, incorporating resistor 454, to
:., . ;
ground through lines 300, 288 and 290. Line 456 is
coupled through a resistor 458 to the positive side Or
the battery power supply. As line 456 is so coupled
; 20 to ground, a capacitor 460 is discharged through re-
sistor 454, thus altering the voltage level at line
456 from a high to a low value. Line 456 is coupled
to theinputs Or one NAND gate of component 306. The
transition at line 456 causes line 462, extending
~rom its associated NAN~ gate output, to assume a high t
value which is directed to one inputside ofa NAND gate
.: ' , , ., ~ . ~
,, . ~ - - .
,
1~153~6
-44 -
wlthin four gate component 310. If the opposite input
to that gate at line 316 is high, a resultant low
signal is fed through line 464. It should be noted,
however, that when line 314, connected to line 316, is
low, an off start cycle will have been commenced, for
exampleg through switch S9. As ~hown at level V in
Fig. 5, a momentary depression of switch S10 will have
no effect on a normally progressing off start cycle.
Assuming, however, that line 314 is high7 a resultant
10 low output is developed at line 464 which is converted
to a high value at component 318 for presentation a-
long line 380 through line 382 to the set input of the
uppermost flip-flop within component 326. The earlier-
described signal transition at the Q and Q outputs
thereof, respectively, at lines 360 and 328 is carried
out to cause the system to carry out a cycle. It may
be noted that the transitions at the latter flip-flop
are represented at levels VIII and IX in Fig. 5, and
for the instant operation at column B thereof.
As discussed in detail above, the electronic
logic of the controller serves to selectively energize
the tractive electromagnetic actuators of-a valve
arrangement retained within the housing of controller
60. This valve receives relatively low pressure gas,
i.e. 25 p.s.i.g., through lines 64 and regulator 66 as
described in connection with Fig. 1.
- -
"- ,
lllS3~6
-45-
Referrlng to Fig. 6, a schematlc portrayal
of the operation and components of such a valve are
revealed. In the figure, ~ main valve body is shown
at 500 whlch includes a cylindrical valve bore 502
associated in gastransfer relationship with ~ive
conduits. In the latter regard, gas output conduit
504 extends through a threaded connector 506 to be
coupled with the diaphragm of motor valve 34. Venting
conduit 508 will be seen to vent the diaphragm of the
10 motor valve 34 to the atmosphere, while gas input con-
duits 510 and 512 serve to selectively vent bore 502.
A gas lnput conduit 514 extends from a gas distribution
condult present as an elongate bore 516 which, in turn,
is associated through a conduit 518 and threaded con-
nector 520 to the noted input of~gas under pressure.
Bore 516 also communicates through two transversely
disposed control outlets or conduits 522 and 524 with
electromagnetically actuated valves shown respectively
in schematic fashion at 526 and 528. Valves 526 and
20 528, in addition to communicating and gas transfer re-
lationship with respective conduits 510 and 512 also
communicate in-atmospheric venting relationship with
venting conduits shown, respectively, at 530 and 532.
Slidably positioned in bore 502 is a
shuttle plston 534 which, depending upon the vented
status of either of conduits 510 or 512, assumes a
`., .
.~ .
3~6
4 6
termlnal positlon serving elther to dlrect pressurized
gas from lnput 520 into conduit 504, or to vent the
motor valve 34 diaphragm through conduit 508. Shuttle
534 ls formed having three spaced, groove-carrying
circular flangeæ 536, 538 and 540 ~ the centrally dis-
posed groovesof which respectively retain 0-rings 542,
544 and 546. These flanges define, with bore 520, two
ad~acent gas flow regions.
The schematic representation of valves 526
10 and 528 reveals that each contains an inductive wind-
ing, shown respectively at 548 and 550, and an assocl-
ated poppet, respectively revealed at 552 and 554.
Poppets 552 and 554, respectively, are biased such
that they tend to normally close off respective con-,
dults 522 and 524. Upon energiz~tion of an associated
- winding, the appropriate poppet 552 and 554 serves to
block off a vent at 530 and 532.
In the orientation shown in Fig. 6, neither
winding 526 nor winding 528 is energized and gas under
20 pressure may enter through fitting 5?0, conduit 518
and pressurized bore 516. The pressurized gas then
flows through conduit 514 across shuttle 534; through
conduit 504 and fitting 506 to pressurize the dia-
phragm of motor valve 34. When winding 550 is ener-
gized or pulsed with current, for example, for about
100 milliseconds, poppet 554 seals conduit 532 and
.. . . ~......................................... . : . ~
.. .
S3~6
, . .
-47-
pressurized gas flows from bore 516 through condults
524 and 512 to enter one end of bore 502 and drlve
shuttle 534 to a posltlon abuttlng'the outlet of con-
duit 510. In thls orlentation, a gas flow circuit is
presented permitting fitting 506 and conduit 504 to be
in gas flow relationship with condult 508 which is
vented to the atmosphere. Accordingly, pressure is re-
moved from the diaphragm of motor valve 34. Subsequent
energlzatio~ of w,inding 548 of valve 526 causes conduit
. 10 530 to be closed and the pressurization bore 502 from a
path including conduit 510 for another pulsing interval.
Shuttle 534 moves accordingly to the position shown in
Fig. 6. Typicalof~the types of tractive electromagnet-
lc actuated valves which can be utilized at 526 and 528
ls a valve marketed by Clippard Instrument Laboratory,
Inc., Cincinnati, Ohio under the model designation
EV-3MLP.
A more practical and preferred embodiment of
the schematically portrayed valve at Fig. 6 is illus-
20 trated ln connection with Figs. 7-9. In referring to
' those flgures, components having common designations
between those figures in Fig. 6 are represented with
ldentical numeration but in primed fashion. Figs. 7-9
' reveal the presence of a main valve body 500' to which
are coupled electromagnetically actuated valves 526'
and 528' having a structure similar to the above-refer-
enced exemplary valve. As before, a principal bore
'-.' ~ '
.
.
.
lllS3~6
-48-
502 ' ls formed ~ithln the body 500 ' and is secured by
two end pugs 556 and 558. Plugs 556 and 558 are re-
tained in gas sealing relationship with the surface of
bore 502 ' by being formed with the approprlate grooves
and O-rings represented respectively at 560 and 562.
Additionally, the plugs are bored at about a 30 angle
with respect to horizontal to provide the earlier-
described conduits 510 ' and 512 ' . These conduits lead
to the respective tractive electromagnetically actuated
10 valves 526 ' and 528 ' . Looking to Fig. 9, a valve as at
526' is revealed in more detail. Note, that the valve
ncludes an inner connecting body ring 562 which serves
to retain a poppet 564 within a spring like disk 566.
Disk 566 normally retains poppet 564 against conduit
522 ', i.e. normally closed. The opposite side of the
disk 566 shows a component 568 which retains the vent-
ing conduit 530 ' in position for closure upon the ener-
gization ^f ?n elerfrom?gnPf~c w~n~ng ~70'. Disk ~66
contains an opening 572 for permitting the venting of
? gases t~rough conduit 530 ' at such time as the valve
winding is energized. Additionallly, the valve is
~ormed having at least one conduit as at 574 arranged
for gas transfer communication with bore 510 ' ~ Fur-
ther, the valve incorporates a threaded connection 576
which, as revealed in Fig. 7, provides for its coupling
with elongate bore 516 ' .
:'' .
:
.... . . . . . .
: . .,
- . . . ,, , . -
- ... . : . ~.
- . . .
3~6
-
-49-
Flg. 7 shows the valve ln a ventlng orlenta-
tion wherein gases under pressure applied at connection
520' and enterlng bore 515', are bloc~ed at condult ~ -
514'. Should the winding 570 of valve 526' be ener-
gized, however, disk 566 is retracted toward the wind-
ing and vent 530' is closed. This permits the passage
of gas thr,ough the valve and its conduit 574 into bore
.510' to cause the piston 534' to move to the right and
alter cycle status.
Since certain changes may be made in the above
system and apparatus without departing from the scope
of the invention herein involved, it is intended that
all matter contained in the above description or shown
ln accompanying drawings shall be interpret~da,s illus-
tratlve and not ln a limiting sense.
... .
.
